Typewriting machine, typesetting machine, and other keyboard instruments



July 25, 1944.

A. T. CAHILL ANDv OTHER KEYBOARD INSTRUMENTS- Filed Feb. 3, 1938TYPEWRITING MACHINE, TYPESETTING MACHINE,

l0 Sheets-Sheet l a WA4@ July2`5, 1944- A. T. cAHlLL TYPEWRITINGMACHINE, TYPESETTING MACHINE,

AND OTHER KEYBOARD INSTRUMENTS Filed Feb. s. 1938 1o shets-sheet 2 July25, 1944. A. T. CAI-ULL 2,354,196

TYPEWRITING MACHINE, TYPESETTING MACHINE,

AND OTHER KEYBOARD INSTRUMENTS l0 Sheets-Sheet 3 Filed Feb.`3, 1958 July25, 1944. A. T. cAHlLl.

` TYPEWRITING MACHINE, TYPESETTING MACHINE,

AND OTHER KEYBOARD INSTRUMENTS lO Sheets-Sheet 4 Filed Feb. C5, 1958Fij- 4 July 25, 1944.

- A. T. CAHILL TYPEWRITING MACHINE, TYPESETTING MACHINE,

AND OTHER KEYBOARD INSTRUMENTS l Filed Feb. 5, 19:58

10 Sheets-Sheet 5` `Iuly 25, 1944. T. cAHlLL TYPEWRITING HINE,TYPESETTING MACHINE, AND OT KEY RD INSTRUMENTS 10 SheeLs-Sheet 6 'leaf.3,1

A. T. CAHILL. 2,354,196 TYPEWRITIN MA TYPE ET ING MACHINE,

AND O RD RUMENTS r `1 3 38 lO Sheets-Sheet '7 H K ed Jiy 25, 1944.

DOUBLE REVERSE Julyzs, 1944. A CAH 2,354,196

LL TYPEWRITING MAC E, TYPESETTING MACHINE,

AND OTHER KEYBOARD INSTRUMENTS Filed Feb. 3, 1958 10 Sheets-Sheet 8 July25, 1944. 4 A. T. cAHlLL 2,354,196

TYPEWRITING MACHINE, .TYPESETTING MACHINE,

AND OTHER KEYBOARD INSTRUMENTS Filed Feb. 3, 1958 l0 Sheets-Sheet 9 July25, 1944 A. T. cAH1| 2,354,196

TYPEWRITING MACHINE, TYPESETTING MACHINE,

AND OTHER KEYBOARD INSTRUMENTS Filed Feb. C5, 1958 l0 Sheets-Sheet l0 myZ 11s/VENTO A TTORNEYS.

Patented July 25, 1944 [UNlrEo STATE 'Arthur-r. Cahill, Weehawken, N J.l Application February 3, 193s, serial.No.1ss,5o2

21 claims. (01.197-141. n i

My" present invention relates to keyboard instruments,especially-typewriting machines, and has among' its principal objectsthat of providingnovel and improved means facilitating simpleyand rapidbut less energy-consuming operatio'nfonithe partof thev typist, suchmeans being in'large part based' on thefrcognition and availing ofcertain vowel and consonant frequencies and relationships. l Otherobjects will be apparent from the following description in connection,with the dra'WingaincIuding. various novel provisions for quietoperation, power actuation, legato action, automatic determination ofcertain letter and spacer sequences,` and other features andcombinations thereof.

'In the drawings illustrating by way of example certain embodimentsofthe invention:

Fig. -1 is a longitudinal section through the mechanism as a Whole, asupon the line l--I of Fig.4;

Figs. 2 and'3, the latter a continuation forward of Fig. 2, togetherpresent a similar longitudinal section corresponding to a major portionof Fig. 1, on twice the scale of that gure;

Fig. 4 is a horizontal section on thev line 4 4 of Fig. 1', with certainparts omitted for clarity;

Fig. 5 is a detail elevation and perspective View of a rear portion of akey reed and associated parts;

.Fig., 6 1 is a transverse vertical section taken immediately inside theiront Vend of the machine frame, as on the line 6-5 of Fig. 4;

. Fig. V'7 is a perspectivedetail of part of the holding and releasingmechanism for the thumb keys;

Fig. 8 is a detail ofthe key reeds used on the fourth row of keys, therearmost row on the universal keyboard;

Figs. 9 and 10 are details of the key reeds in the third row of keys,the second row from the back, showing. certain reed extensions foroperating thevowel and consonant frames;

Figs. 11 and 12 are details of `the key reeds in thesecond row from thefront, also showing eX- tensions for operating the voweland consonantframes;

Fig. 13 illustrates the key reeds in the firstv orfront row of keys,including certain extensions for operating the consonant frame, therebeing no vowels in this row, in the form shown;

ffFigs. 14, 15 and 16 are similar views of thumb key, space bar andenlarger key reeds respectively;

s PAT MACHINE. TYPESETTING MACHINE, yAND l0TH ER :KEYBOARD` of variousmodifications ofthe keyboard nin accordance with the invention; i f 1;-.g a Fig. 24 is a wiring. diagram typically illustrat-` ing variouscircuits-'associated with the electrical'- ly operated form ofthefinvention; f I f Fig. 25 is a detailed elevational view 'of Varnoisesuppressor applicable to .one form of'v carriage mechanism; Figs. 26 andZ'Iare Tgdiagrarns;-explanatoryof speed increases resultant from thelegato-amilonv feature of the invention, utilizing p8@ la' anda .i1/2overlap respectively; f-

. ,i jg Fig. 2.8 (on the `sheet-:with:diagrammatic Figs. 26. and 27) lis a viewfcorrespondingto Fig.; 1, illustrating a duplextypewritersimilar in .general principles to the power-operatedftype of said Fig. 1.but in this instance manually operated;

Figs. 28A and 28Bl are front .and-side detail elevational views ofispacinggmechanism applicable either to thepower orthe, manually oper..atedformoftypewriter..

V.Before describing the illustrative vembodirrlents of the inventionwithmoredetailed reference to the drawings, the following. .additionalintroductory and generalv statementas toobjectivesand principles of theinvention should aid in' understanding its substance andscope Desirably,and as here shown, the typewriting machines concerned incorporate,theaccepte ed standard and so-calledv universal keyboard,- and ingeneral 4form vand arrangement resemble such type of machine.Power--operatiom` con,- veniently e1ectromagnetica1ly,isa preferredfeature, with the operators lingers merely-controlling the applicationor release of. the power, but it is not indispensible as regards variousaspects of the invention, a manually-operated form of machine beingincluded I.in the present` disclosure. -A shallow depression` of thekeys anda legato touchupon them vis contemplated, with an associatedlegato, overlapping vand Veasy rhythm-action, less tiresome fortheoperator yet productive of more typed work in a given time.

The invention involves the Yproduction o; aplurality of printingelects.I `such as two letters or a letter and a space, simultaneously.Thisinvolves the provision of a number vof extra or specialkeys whichherein forconveniencewill generally be referred to as `thu'rnbkeys sincedesirablilr llheyare. positioned -for vconvenient operation by thethumbs, it being understood, however, that the term thumb is foridentification rather than lim-v itation, as the .extra keys may beotherwise operated.. While the number of such keys may be Figs. 17 to 23inclusiveare elevational views 56 considerably varied, an eiectivenumber is six or at one action instead of three. The determination L asto which of two available letters shall be ef'- automatically made bythe'machine itself, in general a consonant automatically following andthe capacity of the particular operator permit.

In accordance with the invention it thus is made possible, while usingthe present touch typewriting system, to print letters in pairs, insteadof singly, simply by printing the first letter, the primary or leadingletter, with a finger on the universal keyboard, just as it is done now,and the secondary or following letter ofthe pair simultaneously, bydropping the thumb onto a thumb key as the finger is dropped onto theiin- 'ger key, the thumb and linger acting simultafected by a givenspecial thumb key is largely"l"'il1e0uS1Y, andthisrotation of actionswill be conctinued to the end* of the word, no matter how long a vowel,and a vowel a consonant, all with n the avoidance of ever having todepress more than one key at a time to produce one individual letter, asordinarily required where a number ofV`l keys less than the number ofletters of the alpha-` bet is used. In printing letters'in pairs the'first letter of such pair is taken'leon'theuniversal key-1y boardwhosekeys are always live,"in contrast to the special or thumbkeyswhich'iare deadV or inactive until conditioned by the printing of aletter on theuniversal keyboard.

Other`A inventive features will be apparentfincluding those ofconvenient keypositioning and the provision 'fr'substi al noiselesspower-operation. 1 ',:vfn 1,541' y 'Y Without here setting' outin'detail the various facts resultant from an analytical'study ofthenature'of wordsand 'theirspellir'ig in the English language, and in viewof which th'e duplex method' of operation here involvedis'made'practicable, it is suicient to note that'tlie' letters of ythealpha-l bet may be `c1assifie df as "vowels or fcharacters which behaveas vowels; as to frequency of occurrenceand probability of 'following aconsonant vowel type letter and the Iother a consonant or a consonanttype letter. i,It will be understood thatV generally herein the termsvowel and consonant include not only those letters 'as' commonly con-lsidered but alsoth'ose which tend'to act like them respectively, as to'their Avowel-following or their consonant-following frequency. And inthe provision of my special or Ithumb keys advantage v also is taken ofother noted characteristics of the' English language, such asethelikelihood of cer'- tain letters to occur Amore often or come in theeven numbered positions, that is, as'the second, fourth, sixth, eighth,etc.,'letter of aword.

While the facts such as mentioned asto letter occurrence were largelyappreciated and to some extent availed of by my late brother, Dr.Thaddeus Cahill, in the provision of his machines of the combination orpermutation type, those machines frequently required the use of two ormore lingers for vthe production of a single letter, and involved highskilll and a long period of special trainingfor the operator. My presentinvention, however, eliminates any such plural keying for al singleletter and provides a machine including a standard or universalkeyboard, always available to any operator accustomed to such keyboardbut also incorporating my special or thumb keys for duplex work, theperformance' of which may be' acquired gradually or otherwise ascircumstances it may be, thedirst, third, fifth, seventh, etc., lettersbeingY taken on the universal keyboard, and

'the second, fourth, sixth, eighth, etc., letters bef ing depressedvsimultaneously by the thumb when the nger depresses the finger key onthe universal keyboard. Operation in accordance with my invention isfurtherfacilitated by an exceedingly light touch andshallowdepressionvof the keys, as well as by an easy legato-actionfwhichpermits thek operator to keepy the fingers on the keys after the lettershave been printed and does not necessitate the quick, jerky, staccato.action to get off the keys instantly,which is necessary on the presentmanuallyv operated machine.

List of partsand theirvreferecenameralr In the following specificationand the accompanying drawings, similar-numbers or letters are used forsimilar parts: f I, I, are the key reeds of the universal ma-s chine.

I, la, are the nger keys on -theukeylreeds of the universal keyboard.lb, Ib, are the extensions on the key reeds that operate the voweloperated consonant releasingA contact frame 6I. Ic, lc, are theextensions on the keyreeds that operate the consonant operated vowelreleasing contact frame 60.

ld is the tabulator key reed. Ie is the back spacer key reed. f I. f

2, 2, are the extensions on the key reeds fm-I the jacks. M l,

3, 3, are the jacks. f

3a, 3a, are the shoulder pivots which connect the jacks 3 with the bellcrank levers 4. Y.

3b, 3b, are springs connecting 3 and 4.which return 3, 3, to theirnormal positions.

4, 4, are the bell crank levers.,

lab is the rod or fulcrum on which the bell, cranks 4, 4, and the levers5, 5, are mounted and oscillate.

4b, 4b, are pins in 4, 4, which push the levers 5, 5, ahead of them.

5, 5, are levers mounted on 4a.

5a. 5a, are the shoulder pivots which connect the levers 5, 5, with thepush rods 6, 6.

5b, 5b, are returning springs which return the levers 5, 5, push pieces6, 8, and pendants l, l, to their normal positions.

5@ is a milled bar mounting for the bell cranks 4, 4, and levers 5, 5.

5d is a thin strip of metal to which one end of the springs 5b, 5b, areattached.

6, 6, are the push rods receiving motion from the levers 5, 5, andimparting it to the-pendants 1, 1. l

l, 1, are pendants, thrown over the motor frame 26 by the push rods 6,6.

la, la, are shoulder pivots connecting the pend` ants l, 1, with thepush rods 6, 6. l

n Ib, 1b, are the pivots connecting the pendants 1, 1, with 'the levers8, 8.

V8, 8, are the levers which receive movement from the pendants 1, 1, atone end and impart it through the pull-down wires 9, 9, connected at theother end, to the levers I0, I0, which, through the wires II, II, impartmovement to the type bars I2, I2.

8a, 8a, are returning springs which return the pendants 1, 1, levers 8,8, and pull-down wires I2@ is the semi-circular Wire fulcrum on whichthe type bars I2 are mounted and oscillate.

I2b, I2b, are the type bar returning springs. l r is the two polerotary-motor magnet.

.'2Iis the oscillating magnetic armature which,

through the motor frame, imparts motion to the t pendants 1, 1. It also,through the arm 21 on the motor frame shaft and the push rod 28,connected to said arm and to the spacing mechanism, imparts motion tothe spacing mechanism. It also, by means of another arm, 29, on themotor frame shaft, imparts motion to the knockout frames 3I and 5I,through the push rod 38. It also, through another similar arm 95, andthe push rod 96, imparts motion to the bell crank 91 whose pawl 98constantly winds up the motor spring for the revolving platen orcarriage.

I2Ia is a stud or pivot set fast in the armature 2| and connecting 2|and 2IC.

2|b is a, cloth felt`bushing between stud 2Ia and connecting head 2l tosuppress noise.

2I is the connecting head of non-magnetic metal.

2Id is a check vnut on 'connecting' rod 25.

22 is a stud set fast in the frame of the magnet 20, on which thearmature 2I revolves.

23 is a bushing of brass, bronze or other nonmagnetic material forcedinto the armature 2I and reamed to fit the stud 22.

24 is the Whistler spring to return the parts to their normal positions.

I25 is an adjustable connecting rod, connect--l ing the armature 2I withthe motor frame 26.

26 is the motor frame.

26.El is the connecting head connecting 25 and 26.

26b is the stud in motor frame 26.

2.6c is the cloth felt bushing.

21 is an arm on the motor frame 26, which actuates the spacingmechanism.

21a is a pivot connecting the arm 21 and push rod 28.

28 is the adjustable push rod whichv operates the spacing mechanism.

28a, 28a, are connecting heads screw-threaded on the rod 28 for betteradjustment.

28b is a lock nut on 28.

29 is another arm similar to 21 on the motor frame shaft to operate theknockout frames 3-I and 5I.

29a is a pivot connecting 29 and 39.

`3|] is the adjustable push rod which connects 29 with the knockoutframe 3l.

30a, 30a, are the connecting heads `on the push rod 3|).V

3Ilbvi`s the pivot connecting the push rod 30 and knockout frame 3I`;

30, 3|I|c are locknuts on rod 38.

30d, 38d are connecting heads for rod 30.

2I is the first or universal keyboard knockout frame.

3Ia is the shouldered pivot connecting 3I and 50.

3lb is the tube ory rod to which the upwardly extending arms ofy theU-shaped piece 3I are made fast so making the whole into a tight andstiff frame.`

33 is the contact frame lying over the tails of the bell crank levers.It is operated by the keys of the universal keyboard.

33a is the Whistler spring which returns frame to its normal position.

48, 40 are the thumb key reeds. 40a, 40ab are the tablets attached to40, 48 forthe thumbs to operate.

4I, 4I, are the key extensions on the key reeds 48, 4I), which operatethe jacks 43, 43.

v 42 is the double spacer or space enlarger thumb key reed;

42,2L is an extension on 42 to operate the specially-long jack 42h.

'42*7`is the specially-long space enlarger jack for 42.`

. 43, 43 are the thumb key jacks.

43a, 43a, are the shoulder pivots connecting jacks 43 With bell cranks44.

43h, 431 are the springs conecting the jacks 43, 43. with the bell cranklevers 44, 44 and which return the jacks to their normal positions.

44, 44, are the bell cranks.

44a, 44a, are the rock shafts on which the bell cranks 44, M., aremounted fast, while the levers 45, 45, also mounted on these shafts, arefree to oscillate. I

44h, 44h, are the pins which shove the levers 45, dlbefore them.

44 is a lever, which, under the action of the jackl 43, moves the spring18 into contact with the; point 18h.

45, 45, are levers which shove the bushings 46h, 46h, ahead of them.

46, 48, are push rods which operate the vowel pendants represented bythe thumb keys.

45a, 46a, are extensions on the push rods 46, by which the frame Ibholds back the thumb key operated vowels until they are released by theaction oi' the magnet 68a.

46h, 4811, are bushings which are moved by the levers 45, 45, andcompress the spiral springs 46.

46C, 46C, are spiral springs sliding on rods 46d, as bushings 4Gb, 4Gb,compress them.

46d, 46d, are rods made fast to rearward bentover ends of 46, 46, and41, 41, and on which the springs 46C, 46% slide.

41, 41, are the push rods which operate the consonant pendantsrepresented by the vthumb keys.

' 41a, 41a, are extensions on push rods 41, by which the frame 6 lbholds back the thumb key operated consonants until they are released, bythe action of the magnet SIe.

49 is a latch or pawl to hold 5I! in its second position. p

5I) is a push piece or link connecting knockout frames 3I` and 5I.A

5l is the second or thumb key knockout frame.

5I is a shouldered pivot connecting the link 5D and thumb key knockoutframe 5 I.

5Ibis the tube or rod t0 which the upwardly 'extending arms ofi theU-shaped piece 5lv are made fast, so making the whole into av lightstiff frame.

5Ic, 5|d and 5l@ are circuit closing arms fast on I 1' 5|c closes acircuit at 11.

5ldcloses a circuit at 12; and

Sie closes a circuit at 14.

52 is an oscillating frame, consisting, as shown in the drawing, of arear tube 52a, carried by arms 52C, 52C, fast on the front tube 52h. Thefront tube 52b is set on hardened trunnions. To the front tube of thisframe are attached fast three arms, one of which is an upwardly andforwardly extending arm, 52d.

52dd is a shouldered pin set in 52d. l

Another shorter upwardly and forwardly extending arm, 52e, is attachedto this frame, which carries a grooved wheel 52f, at its outer end, onwhich the connecting rod 50 rolls, when the universal keys are used, andwhich drops out of the way and allows the connecting rod 50 to dropafter a letter has been printed on the universal keyboard, and beforethe following letter, represented by a thumb key, has printed. The thirdarm-the downwardly and forwardly extending arm 52E-pulls the speciallylong jack 42b for the thumb key space enlarger bar off the exten-v sion42a, on the thumb key space enlarger bar 42.

52a is the rear tube of this frame.

52h is the front tube of this frame.

y 52C, 52, are the side bars of this frame.

52d is an arm of this frame which controls the latch 49.

52e carries the grooved wheel 52f.

52f is the grooved wheel carried by 52e.

52g is the arm that controls the movements of the space enlarger jack42h.

53 is the contact frame for the thumb keys, actuated by the bell cranks44.

53a is the Whistler spring which returns it to its normal position.

B0 is the contact frame which is actuated by the consonant keys andwhich controls the action of the magnet 60a, and releasing frame 60h,which releases the vowels.

Si!)a is the vowel releasing magnet.

Gllb is the vowel releasing frame.

66C is the wire connecting the rotating armature of lillaL with theframe 60h.

60d is the arm on the releasing frame 60h, which closes the circuit ofthe space enlarger magnet 90.

BI is the contact frame which is actuated by the vowel keys and whichcontrols the action of the magnet 6|a and releasing frame SIb whichreleases the consonants.

' 6|@L is the consonant releasing magnet.

lilb is the consonant releasing frame.

GIC is the wire connecting the rotating armature of @la with the frame 6Ib.

6Id is an arm on the releasing frame Blb, which closes the circuit ofthe space enlarger magnet 90.

62 is the stop on which the releasing frames l!)b and Bib normally rest.

63, 63` are key reeds for the single space bar. One is seen in dottedlines back of the thumb key reed 40 in Fig. 3. Near the front they havedownward extensions which are connected into a frame by being made fastto the rod 63a.

63a is the rod on which 63, 63 are fastened.

54 is a piece of insulation on said frame.

.65 is the key reed fulcrum bar.

Concerning the contact springs, points, supports, screws, nuts and lugsfor same' ,"1

The numeral and a is a contact point carried by the spring, y

The numeral and bis va contact point fast ln the end of a screw. I

The numeral and c is the screw, which carriesv the contact point.

The numeral and d is the insulated support for the screw. v The numeraland e is the lug for soldering the wire into.

The numeral and f is a locknut for holding the screw in whatevervposition it Amay be a cl.

justed. Y

Since micrometric adjustments are necessary where a number of actionstake place at great speed and which have to be timed very accurately soas to follow eachother in proper sequence,A contact points set in screwsare used in all cases. In some cases in the drawings all the parts areyshown, and in others, where there is lnot room.l

they are illustrated diagrammatically.

'l0 is the contact carrying spring which the downwardly extending arm ofthe contact framey 33 pushes over against the fixed contact 10b,

so closing the main circuit of the motor magnet` ZO-the circuit which isclosed by'the keys o the universal keyboard.

The thumb key operated motor magnet circuit is not a simple circuit.circuit with four breaks in it, as follows:

1| is the contact carrying spring which the downwardly extending arm ofthe thumb key contact frame 53 presses'over against the contact point"Hb, thus closing the first .gap in the' thumb key circuit of the motormagnet 20.

12 is the contact carrying spring which is pressed over against theiixed contact 12b, un'

der the impulse of the arm 5Id, of the thumb key knockout frame 5|, thusclosing the second gap in this circuit.

` 13 is the contact carrying spring pressed over against the xed contactpoint I3b by the motor' frame 26 as it returns to its normal position,thus closing the third gap in the circuit of the motor magnet 20.

'I4 is the contactcarrying spring which,l u n'-- der the second impulseof the arm 51e, carried by the thumb key operated knockout frameA .'ql',

is 4pressed over against the xed contact point 14h, and thus closes thefourth and last 'circuiti of the thumb key operated circuit to the motormagnet 20.

15 is the spring which closes the vcircuit of the space enlarger magnet9|). This is a simple circuit, with only this one break in it. It isoper-v ated by the universal keyboard keys only.

The releasing magnet vcircuit is also a compound circuit. lows:

16 is the contact carrying spring which, un-

der the impulse of the downwardly extending It is a compound" Ithas twobreaks in it, as folarm of the thumb key actuated contact frame 53.,closes the common` return of the releasing magnets |50a and (ile.Y Thiscircuit has a break in it at 11, whichr is closed later.

11 is the. contactcarrying spring which, un-

'derthe impulse of' `thearrn SIC,` of the thumb key operated knockoutframe closes the common return of the releasing. magnets |30EL and 6 la.The space enlarger circuit is. also a compound circuit. It has twobreaks in it, as follows:

18 is the contactv carrying spring which, under the impulse of the spaceenlarger key, trans mtted through av jack 43 and a lever 44C, is

moved against the contact -point 18h, and so closes theA common returnof the space enlarger magnet 90 `at this point. ,There is a break inthis circuit which is closed later, at 19.

19 is the contact carrying spring which, under the impulse. of the.upwardly extending arms, .either 68d or Bld, both of which are operatedby the releasing magnets |50a and la, closes the commonreturn of thespace enlarger magnet 98.

88 is the contact carrying,` springv which, under -the impulse of thevowel operated consonant releasing frame 6|., ,is` forced into contactwith the contact point 80h-, so closing, the circuit of the,uvowelfoperated consonant releasing magnet Gla,

so releasing the vcontact with two contact points. `The contactors arenormally spring pressed against the contact points, 82b and` 83:11, inthe rearward position,

and s o close the circuits of the releasing magnets 60a and 6|, When thedouble reversing lever is` pressed backward by the. thumb, thecontactors are thrownover into contact with the other. set of Contactpoints, 82bh and 83h", whose wires leading, to they magnets have beenreversed Y so. that a different: magnet acts, when the spring is in theforward Iposition, from the one which aotsvwhen it isA in the rearIposition.

84, is the contact spring, which, under the action of the single spacer;is thrown against the fixed contact point 84", so closing the circuit,of the motor magnet, which acts without print-ing a letter to make` ablank space.

, 85 is; the knockout framefor the thumbr keys and double reversingholdv down` dogs.

8,5,aA is; the shaft for above frame.

851 is4 the upper, arm of frame which releases the thumbJ keys- 8,5.cis, thel armof the.- frame 85, which releases the. double reversinglever. 85d is, the lower arm ofthe frame 85, which is pulled by the pullrod 86.

85e isr the lpin fast. on; the arm 85d.

86k is, the, pull rod actuatedby the knockout frame. y 85,.a is theconnecting headfor the pull. rod 86.

81, 81,.are.the dogs which hold theA thumbkeys down.

81a is. the shaft on, which` the dogs 811 and 81c are pivoted. y 8,1b isthe. WhistlerV springv for the dogs 81 and 81. 81 is the.

y hold down..v dog for the double reverser.,

lacks.

88 is a double reversingv lever.

88a is the pivot.

88D is the casting to which attached.

38c is the latch for the lever 88.

8S is the finger release for thumbfkeys and double reversing lever.

98 is the space enlargerzmagnet.

9| is the oscillating plate which carries the spacing mechanism. l

9 |21, Sie are the bearings on which it oscillates.

92 is the fly dog.

92a is the shoulder -screw on which the ily dog isV mounted.

92b is the movable fly dog stop.

92 is the set fly dog stop.

92d is the spring that actuates the ily dog.

the rever as. is

93 is the carriagereturn noise suppressor and spring shock absorbingcasting',

93a, 93a, are adjusting screws for springs 94 and 94a.v

93h, 9,31? arev adjusting screw` locknuts..

94 is the stronger shock absorbing and noise suppressing spring.

94a is the weaker shock absorbing and noise suppressing spring.v l,

The following num-bers refer to my manuallyoperated'. duplerc typewriter|5|, |5| are the key reeds.

ISI", |5|b are the extensions on the key reeds that operate theV voweloperated consonant releasing frames.

|5|c, |5|c are the extensions on the key reeds that operate theconsonant-operated vowel releasing frames.

|52, |52 are the key reed exten-sions for the |53, |53' are the jacks.

|54, |54, are the bell crank levers.

|5422 |54a are the rods on which the bell crank levers are mounted.

|55, |55, are the lbell crank operatedv levers.

|555, |55a are thel shoulder pivots in levers |55.

|5511, |55b arethe lever returning springs;

|55c is the milled bar mounting for the bell crank levers.

|55d is a thin rnetal strip tov which the springs |55b are attached.

|56, |56 are thepush rods that operate the levers |51-, |51; Y

|51, |51 are-thelevers whichpullthe type bars.

|6|, |6| are the wires which impart motion from the levers |51, |51. tothe type bars |52, |62. l

|62, |52 are the type barst |63 is the adjustable pull: rod whichoperates the spacing mechanism.

|84 is the bell crank'lever which operates the knockout frame.

|65 is the knockout frame.

|66 is. the spring which actuates the knockout frame.

|1|, |1| are the thumb key reeds.

|12, |12 are the keyf reedi extensions. for the jacks |13, |13 whoseupward extension operates the selector for space enlarger.

|13, |13 are the jacks.

|14, |14 are the levers.

|143, |14a are the rods on which the levers are mounted.

|15, |15 are the Whistler springswhich push the rods |11 through thelever |16..

|15V is the lever that pushes the rod |11..

|11 is the push rod which operates the vowels represented by the thumbkeys.

|18 is the push rod which operates the consonants represented by thethumib keys.

|19 is the holding frame for the consonants and vowels.

|80 is the releasing connecting lever from the knockout frame |65 to theframe |19.

|8| is the [bell crank lever which operates the knockout frame |82.

|8|a is the spring that returns the bell crank |8| to normal.

` |82 is the. knockout frame.

|82EL is the holding latch for the knockout frame |82.

|83 is the actuating spring for the knockout frame.

|84 is the vowel releasing frame actuating lever.

|85 is the consonant-releasing frame actuating lever.` l v f |86 is thepull wire that operates from the vowel releasing frame |84 to the vowelreleasing frame |81.

|81 is the vowel releasing frame.

V|88 is the consonant releasing frame.

|89 is the double reversing lever.

|89ab is the connecting rod from the double reversing lever to the frame|90.

|90 is the double reversing pivoting frame.

| 9| is the double spacer key reed.

,|9Ia is the double spacer key reed extension.

|9|b is the specially long space enlarger jack.

|92 is the special bell crank for the double spacer jack |9 b.

|9297 is the connecting bell crank :between |92 and |93.

|93 is the double spacer push rod.

|94 is the special bell crank for the double spacer jack, which isoperated by the thumb keys. .1949 is the connecting bell crank between|94 and the pull rod |95.

|95 is the pull piece, actuated by |94, which moves the double spacerfly dog stop.

|96 is the movable ly dog stop.

|91 is .the :bell crank which operates the connecting links |919 and 91bwhich pull the double spacer jack |l9|b oflf the key extension |9|a.

|91a is the link connected to bell crank |91.

|911 is the link connected to link |912.

|98 is the knockout frame for the thumb keys and double reversing holddown dogs.

,. |98a is the shaft for above frame.

|98D is the upper arm of frame |98 which releases the thumb keys.

|98c is the arm of the frame |98 which releases the double reversinglever.

-200c are pivoted.

2009, 2009, are the Whistler springs for the dogs 200 and 200.

200c is the hold down dog for the double reverser.

Method of operation Since the underlying principle that makes most ofthese inventions possible is the almost automatic alternating of vowelsand consonants and consonants and vowels, which enables each lthumb keyto produce two letters instead of one, and

each of these two letters in two relations or positions with regard tothe letter that has preceded it, as the letter may follow either a vowelor a consonant, it would, of course, be possible to make thesealternationsor reversals by hand, as will be pointed out later. But thiswould involve a tremendous amount of extra mental labor on the part ofthe operator and a very much more difficult technique, which wouldprobably slow things up so much that there would be no particular gain.It is, therefore, desirable and necessary, if the machine is to be easyto op'- erate and capable of very great speed, to have the machine doall the thinking and all the work in connection with the reversals forthe operator. In other words, to have the machine do it automatically,without any thought or effort on the part of the operator. I accomplishthis as follows:

All the key reeds on the universal keyboard, excepting only the keyreeds of the letter keys, are made smooth on top and bottom just as theyare now, while all the key reeds which represent letters and lettersalone, in the three other rows, have projections upon them which, whenthese keys are depressed, operate one or the other of two contactframes. The key reeds representing the lve vowels, a, e, i, o, u, andthe additional consonants which behave like vowels, such as d, h and y,shown in the top row on the thumb keys in the keyboard drawings, Figs.4, 1'1 and 21, all carry projections, lb, lb, upon them, which are inone line crosswise of the machine, and all of which operate the samecontact frame 6|- the vowel operated frame which closes the circuit ofthe consonant releasing magnet 6| while all the remaining letter keyreeds (those representing the remaining eighteen consonants) carryprojections, upon them, in another line crosswise of the machine, which,when any of those keys are depressed, will actuate the contact frame(iO-the consonant operated frame-which closes the circuit of the otherreleasing magnet 609-the magnet which releases the vow'els and letterswhich behave like vowels. All the other keys on the keyboard, except theletter keys, remain as they are now Without any projections upon them,since no reversals are necessary in their case.

The actions of the key reeds key reed extensions 2, 2, jacks 3, 3, bellcrank levers 4, 4,

levers 5, 5, push pieces 6, 6, pendants 1, 1, levers 8, 8, pull-downwires 9, 9, motor magnet 20, motor frame 26, knock-out frame 3|, spaceactuating push rod 28, etc., are similar to those shown in the patent ofmy late brother, Dr. Thaddeus Cahill, No. 1,197,103, filed November 4,1899, but not issued until September 5, 1916, and which we used in ourelectrical typewriters with such eminent success, and which are capableof almost unlimited speed. They are very simple, inexpensive, direct,positive, and quiet in action. They involve a minimum of simple partsand can not easily Ibe improved upon. In fact, none of the electricalmachines put upon the market since that time approach them in the abovecharacteristics. f

Since this is already a part of the artI will describe it only verybriefly here:

When the operators finger touches the letter key, the key reed in therear of the fulcrum 65 rises, pushing upward the jack 3, which in turnactuates the bell crank lever 4, which revolves-on i" therod 4a, andwhose-'pin 4b, resting v.in Contact with the lever .5,:which is alsomounted and `os cillates on the rod 4a, shoves 'the same before it.

:The 'lever 5, being pivotedrto -the Vpushrod 6,

shoves it 4before it and throws the pendant 1 over .the motor frame 26.Meanwhile, as the rear end of/ the bell crank 4 has been pushed upward,the

.contactframel Fig. 2,l resting-upon the tails of the bell cranks 4.,has been pushed u|pward,'.`andthe downwardly extending arm of thecontact v.frame has closed the circuit of the motor magnet 20, whichpulls up the motor frame 26, bringing it intofcontact with the pendant1, whichhas rbeenlthrown Yover it by the action of the finger,

and shoves -said pendant before it. The pendant 1 pushes up the rearwardend of the lever 8, whose front end pulls down .the pull-down lwire 9,which actuates the lever IB, which in turnactuates the Vpull wire il I,connected to the vtype f'bar I2, which revolves `on the rod |221, and sothrows the type bar against `the platen. Meanwhile, as the motor frame26 has risen, throwin'g up the pendant and through the Ichain'lof beingheld down. This completes the printing of the rstorleadingletter,vthat"which is printed upon the' universal keyboardmachine. In fact, 'the actions are so tremendously fast that they l'arefrequently all completed-letter printed and parts returned to their,-normal positions-before 'fthe operators nger has reached the bottom rof`the depression.

-Coming now tothe action of my special thumb keys: 'The' eight keyreeds, 40, 40, carry extensions 41, 4I, on which therearward'oscillating rod of "the frame 52 rests. The forward `rotatingtube '521 Acafrries three forwardly vextending arms 52d, VA52e and 52.The head ofthe pin 52d@1 set in the top. ofjthe upwardly and Vforwardlyextending .arm 5.21, normally sustains the weight of the pawl l49 andkeeps it out of `contact withthe link 50, when onlythe universalkeyboard keys are'being used. kThe vforwardly and slightly upwardly:extending arm 52e," carries a grooved wheel52f, on y"whichthe link50ro1ls as it moves back and forth under the impulse o f the knock-outframe 3l, jwhere only the universal keyboard keysare being used` Thedownwardly and forwardly'extending farm 52S, withdraws the speciallylong jack 42h, `forthe double space or space enlarger thumb key reed 42.,This is necessary, since ythis 'jack'must work whenever it is desiredto make a'single let- ,"ter and a space together, and the space bar is,therefore ,put down simultaneously with a keyon either the universalkeyboard orthe thumb keys. If, now, thisjack were not withdrawn when thespace enlarger -key isput down in conjunction witha finger `key on theuniversal keyboard marchine, [there would be a space after the 'firstlet- Ater'of the pair had been 'printedand before the `second letter hadprinted. It is, therefore, lnecessary, when printinglettersinpairs,'thatthis jackbewithdrawn so that the Aspace enlargermagnet does-"not Yact until yafter the first letter 'of l'the pair1lfras'printe'd. There are 'two circuits,

"the selected letter tobe'printed.

either `ofwliich actuates the space .enlarger maignet. One is a simplecircuit, `15, controlled iby the 'space enlarger jack 42 alone; theother is a cir.

`cuit with two breaks in it', one of which isclosed at 18, when thespace enlarger key is depressed rinconjunction with a thumb key, and thefinal one'is closed at 19, when either one of the releasing frames Bubor Gib acts, just .before the secondary or thumb key letter prints, allof which will be explained later in more detail.

The jacks 43, 43, are similar in `function to the vjacks 3, '3, in thatthey operate the bell crank levers 44,` 44, which perform the samefunctions 4asthe bell cranks 4, 4, in that, `through the pins 44h, theypush the levers 45; 45,l before them. These, in turn, push the slidingbushings 463,161,

Abefore them, and so `compress the `springs:46c,

46?, since the push rods46 and 41 are held from moving by the releasingframes 661 and lill. When the selected releasing frameacts,v the powerVstored up in the compressed spring, 46, through the push rods 46 or 41,which press against the shoulder pivot5a set fast in 6, shoots theselected push rod -6 before it, and so throws the pendant 1 over themotorframe 26, `ready for printing, when Vthe circuit of the motormagnet 20 is again-closed. The push rods 46,746, correspond to vowels,and the push rods 41, 471, to consonants. Y

Now, sin-ce each thumb key represents two let- Vters,'it is self-evidentthat Vthey cannot both print at the same time and that, therefore, theremust be a holding mechanism or a selecting mechanism, which will holdone `letter back and allow I accomplish this as follows:

Each of my eight thumb keys represents two letters. 'There are,therefore, eight rock shafts,

"them-the' fourth thumb key for the left-hand.

las the levers 5, 5, do, on therod 4a- .It, therefore, lrequires only .avshort rock shaft.

It is here again noted that d is one of the consonants I treat as avowel, and so is releasedby ,the consonant operated vowel releasingframe.

' Therefore, this particular rock'shaft is very short.

Other letters, however, represented by a thumb key, such, for instance,as i and t, lie a considerable distance from each other and also vfromthe thumb key which operates them. These letters will require a longerrock shaft anda different positioning 'of the various arms. It ispo'ssible,

`however, by careful design and proper arrange'- `ment of the letterschosen, to work the eight rock 4sha'fts'into the small space availablein av standard typewriter, as shown in Figs. 1, 2, 3 ande.i

Each of theeight rock shafts, 44a, 44a, carries a'bell crank 4 4, whichis fast on the shaft. They each also carry two levers orarms, 45, 45,which are mounted and oscillate on the shaft 44e, just These levers areso positioned on `the'various rock shafts that `they line up properly`with the particular push pieces 46, 46 and 41, 41, which actuate theuni'- jversal keyboard push pieces 6, 6, that correspond to the lettersdesired.

When a'bell rcrank -44 is operated by onefof the -gjacks '43,'the-twolevers orarms -45,-45,each com'- 'press one of thepsprir1gs"'46C,-46C,-on `the push rods 46 and 41.' When one of thereleasing frames,

operated by its magnet, has released the chosen letter, the compressedspiral spring shoots the push rod 46 or 41, which is pressing againstthe shoulder pivot a, forward, and so shoves the push rod 6 before it.This .throws the pendant 1 over the motor frame 26. Then the motormagnet, whose circuit has again been closed, acts. The knock-out frame5| knocks the jack 43 off the key extension 4| and all the parts againreturn to their normal positions.

The method of operation is, therefore, as follows:

When it is desired to print two letters at a time, the appropriateletter key for the primary or leading letter of the pair is selectedwith the proper finger of the appropriate hand onthe universal keyboard,and the secondary or following letter of the pair is selected with theappropriate thumb, and the two letter keys are then depressedsimultaneously, when the universal keyboard letter immediately prints.

Since both the thumb key and the universal key should go down at thesame time, the thumb key, when depressed, vthrough the jack 43, the bellcrank 44, and the two upwardly extending levers 45, 45, will compressthe two springs 460, 46c, and hold them compressed until such time asthe letter represented by the finger key on the universal keyboard, hasprinted, when one or the other of the frames 6|]b or SIb-the onedetermined by the letter key used on the universal keyboardwill bereleased automatically by the machine, and the push of the compressedspring, now released, will shoot the pendant corresponding to the chosenletter over the motor frame, which will again be energized by currentcontrolled by the thumb keys, and print the selected following orsecondary letter of the pair on the thumb key.

It vwill be seen that the thinking mechanism of the machine, which makesall the reversals absolutely automatically and without any thought,knowledge or action whatever on the part of the operator, lies in theuniversal keyboard, where the vowel keys and the letters behaving likevowels carry projections, Ib, Ib, which operate the vowel operatedconsonant releasing frame. The rest of the alphabet, usually, but notnecessarily all the consonants, carry other similar projections, lc,lying just above the other contact framethe consonant operated vowelreleasing frame 60. These two frames'close the circuits of the tworeleasing magnets lill*ab and Gle, one of which controls the frame thatreleases the'vo'wels and letters behaving like vowels, and the other ofwhich controls the frame that releases the ccnsonants. That is to say,the holding' frames,

A6|)b and 61h, lie normally down on the stop 62, and in engagement withthe projections 46a and 41a, on the push rods 46 and 41, and hold theserods from moving forward under the impulse of their springs, until oneor the other releasing frame is raised by the action of a key on theuniversal keyboard, which selects the proper releasing magnet and sendsthe current through it. The pendant 1 is then shot, over the motorframe, the circuit of whose magnet has again been closed and theselected thumb key letter lis printed. i

When a letter key on the universal keyboard is depressed, it closes thecircuit of one or'the other of the releasing magnets whicha'ctuatethevreleasing frames 60h and SIb, according to whether thecontrolling letter on the universal .keyboard Ais a vowelor a consonant.But since it would not do to have either of the releasing magnets 6l)aor 6|ab act immediately and release its pendant, since vthis would throwtwo pendants over the motor frame and lead to the throwing up of twotype bars with the trouble attendant thereon, it is necessary to have alag in the action of the releasing magnets, which is produced by a break:in the circuit, which is not closed until immediately after theprinting of the primary or leading Aletter on the universal keyboardmachine.

When this break in the circuit is closed, at 11, as it is by theprinting of the rst letter-the leading letter on the universalkeyboard-the appropriate releasing magnet immediately acts,

`pulling up its frame and releasing the selected push rod, either 46 or41, which, under the action of the compressed spring 46c, shoots theypendant 1 over the motor frame, whose magnetic `circuit has again beenclosed at 13 and 14, and

the magnet energized at the same or practically the same time as thereleasing magnet. Due to its much larger size, its action is somewhatslower and gives the pendant plenty of time to getin position. So themotor magnet 20again acts, printing the second letter, and the thumb keyknock-out frame 5|, knocks the jack 43 of! .the key extension 4|, whenall the parts return to their normal positions.

It will be seen that the link 50 is not attached fast to the knock-outframe 3|, but on the contrary, is slotted to allow the shoulder pivotl3|I Ato move back and forth. It also will be noted .key is down, thelink 5|) and the second knockout frame 5| return to their normalpositions in time with the rst knock-out frame 3l. If, however, a thumbkey is depressed simultaneously with a key on the universal keyboard, in

Yorder to print two letters, when the leading letter on the universalkeyboard prints, and the shoulder pivot 3|a in the universal keyboardknock-out frame 3|, has shoved the link 50 and the thumb key knock-outframe 5I, backward, to the halfway position, the pawl 49 is no longersupported by the shoulder pin 52dd, carried b'y the arm 52d, which hasbeen rotated backwards 'and downwards, as the frame 52 has risen.Therefore, the pawl 43drops down in frontk o f the shoulder on the link50, thus holding it and the thumb key knock-out frame 5| in halfwayposition. As soon as the universal keyboard knock-,out frame 3| returnsto its normal position, the forward end of the link 50, which has beenresting on the shoulder pivot Sla, and the grooved wheel 52f, being nolonger supported by either the pivot or the grooved wheel 52t on Awhichit rolls when no thumb key is down, drops vdown until the recessed upperportion comes into contact with the shoulder pivot 3|a again.

Then, as the circuit of the motor magnet 20 is againclosed by the motorframeat 13, the universal keyboard knock-out frame is again thrownbackward, shoving ahead of it, through .the link piece 50, the thumb keyknock-out frame .5|,- which, through the arm 5|e, again closes at 1'4,.the circuit of the motormagnet 20, which again acts, printing thesecondary or following letter represented by the thumb key, and alsoknocks the jack 43 off the extension 4I of the thumb key 40, when allthe parts again return to their normal positions.

In the arrangement of the letters on the thumb keys on the accompanyingdrawings, 41.49% of all the letters occurring in the thumb keyswill bemade by the two thumb keys immediately adjacent to the space bar, thethumb key on the right hand and the thumb key on the left handthe twothumb keys most easy to operatewhile 30.15% will be made on the next twothumb keys (moving outward one key space from the space bar on eachside) which are also very easy to operate. These four keys represent71.64% of all the letters made by the thumb keys, while the next twokeys, moving outwards one key space, represent but 19.15% of the totalnumber of letters made by the thumb keys. The last two keys-the twooutside thumb keysrepresent only 9.21% of the letters made by the thumbkeys. 50.42% will be made by the right hand and 49.58% by the left hand.

It will thus be apparent that the great majority of letters falling uponthe thumb keys, can bemade by a comparatively few keys, so few, in fact,that the thumbs have no difliculty in operating them. Whether thisnumber be six, eight or ten, is optional. I have found however, that theeight keys shown, represent 98% of all the letters which could fall uponthe thumb keys, and that it is easier and faster to make the remaining2% on the universal keyboard than to endeavor to stretch the thumbs intopositions which would be uncomfortable and slower for the ordinarytypewriter operator. A flexible hand can operate ten keys, but on thewhole, I prefer to use only eight, as the best working compromise. f

Of course, it is self-evident that it is perfectly possible and quiteeasy to have two complete alphabets, one represented by the universalkeyboard, and the other represented by thirteen thumb keys, eachcarrying twoy letters. In this case, either eight or ten thumb keyscould be operated by the thumbs, and the other three or rive keys by thelittle fingers. But from my experience, I do not consider that this isas good, as fast, or as easy to operate as the one shown in thedrawings.

Since there are only about 2% of the letters which normally fall upon mythumb keys which we cannot make with eight thumb keys, and since wewould only gain 2% by using the full alphabet of twenty-six lettersrepresented by thirteen keys, which are not nearly so easy tooperate, Iprefer to use eight thumb keys. But I want it distinctly understood thatI do not limit myself to that number or to any particular number. Theexact number of keys used has nothing whatever to do with the inventionshere described.

There are casese-a quite negligible number where we have two vowelsfollowing each other, or a diphthong. There are a good many'more cases,but still a small number, where we have two consonants following eachother. In approximately half these cases, if not in more, thecombination will be broken up owing to the letters being taken in pairs.That is, the second vowel or the second consonant will fall in thesucceeding combination from the rst vowel or consonant. In thecomparatively few cases where they do not, a double reversal has to bemade and the machine has to operate abnormally. That is to say, a vowelfollows a vowel or a consonant follows a consonant.

I accomplish this result by the use of a double reversing bar, as shownin Fig. 21, or a double reversing lever or strip, as shown in Figs. 1,3, 4, 17, 19, 20, 22 and 23. In the case of the bar proper, shown inFig. 21, the thumb is pressed inward over this bar before it isdepressed upon the thumb key and carries the thumb key and the bar downwith it. In the case of the double reversing strip, shown in Figs. l, 3,4, 17, 19, 20, 22 and 23, the thumb is simply pressed inwards a smallfraction of an inch and carries this bar before it the very smalldistance necessary'to` make an electrical contact. This action I havefound by experience is much better and faster, since it is simpler, andthe inward motion of the thumb is more natural, in that it does nothaveA to be nearly so great asin the case of the bar,v

and also in that the two actions, inward and downward, are combined intoone inward, downward action, which is much easier. The action of thisdouble reversing strip or bar is to break.

the normal circuits of the vowel and consonant operated releasing frames60 and 6|, and to close them in an abnormal way, which vvill'justlreverse their normal actions, so that a vowel will follow a vowel, or aconsonant a consonant. One easy method of accomplishing this is shown,and will be readily understoodby referring to Figs. 3 and 24. In thesedrawings, I show a double spring contacter with two spring arms, 82 and83, each of which arms carries a contacter 82a or 83a, long enough tocover two points, and so close a break in the circuit of the releasingmagnets 60 and Sla. Normally, these contactors remain in the backwardrposition and the machine Works normally.v When',l however, the operatorsthumb shoves the double reversing lever inward, the contactors, beingbelowthe center on which the frame oscillates, are shoved forward,breaking the normal connections to the releasing magnets tilla andl,'and establishing new' connections to these same magnets, but thecircuits in the new paths are reversed, so that the ma' chine now actsabnormally. That is to say,the releasing magnet 60a will act instead ofthe magnet Ela, and vice versa. vOf course, similar results can beobtained in other ways, and I by no means limit myself to the methodsshown, but want full protection.

The thumb key and double reversing Zever holding and releasingmechanism.

85 is the releasing frame for the thumbkeys It consists of a shaft 85,to which two upwardly extending arms 85a, 85a, are made fast. These armscarry between them a wire, 85h, which when the frame B5 acts, movesforward, and knocks the dogs Bla, 81a, of the forward extension of thethumb key reeds, 40, 4U. This shaft 85 also carries fast on itself adownwardly extending arm 85d. It also carries an upwardly extending arm85C, which also is fast on 85;

81 is a rod' on which the dogs 81a, 81a, and 81C, are mounted loosely.The Whistler springs 81h, 81h, are also mounted looselyv on the rod 81.One end presses against the dog and the other end against the mainframe.

When a thumb key is depressed, the Whistler spring 8T.b4 throws the dog81a over the extension on the end of the thumb key reed 40, so holdingthe key reed down until the letter on the universal k'eyboardha'sprinted and a thumb key letter has also printed, when the action of thethumb key knock-out frame through the pull rod 86, pulling against thelower'arrn 85d, throws the wire 85b forward and so knocks the dog 87a,off the extension on the front of the thumb key reed, and thus releasessame, which returns to its normal position.

88 is the double reversing lever.

88a is the rod pivoted on trunnion bearings.

88b is a small casting, fast on theV rod 88a, to which the doublereversing lever 88 is made fast. To the lower end of this casting, acatch 88c is made fast.

8'|c is a dog loose on 81, and resting on the upward end of the yarm850, whenthe double reversing lever 88 is shoved inward slightly, sothat the contactors 82 and 83 are in the reverse position. This dog8'lcdrops down behind the catch 88 and holds it until released by the actionof the thumb key knockout frame 5|, through the pull piece 86. When thepull piece 86 acts, the arm 85 is forced forward and upward and soraises the dog 81C, releasing the catch 88, and so allowing the frame 88to return to its normal position.

89 is the hand releasing means, by touching which the operator can, ifdesired, operate the frame 85, and so release any thumb key which hasbeen depressed and the double reversing lever 88 also, if it has beenused.

The single and double spacer mechanism While it has heretofore beenproposed broadly to form the double space after a word simultaneouslywith the last letter, my present invention includes novel means by whicha single and double spacer mechanism can be Worked very simply into thestar wheel mechanism, for use on modern typewriters. 'I'his is shown inFigs. l, 2 and 28, and in more detail in Figs. 28A and 28B, in which 9|is the oscillating plate, which carries the space dogs, their stops,operating springs, etc. This plate is set on trunnions at 9|, 9| a.

92 is the fly dog, pivoted at 92a, which, under the action of the spring92d, is normally pulled backward against the movable stop 92h, whichallows the carriage to move one tooth space at a time. When this stop92b is removed, as it is, by the action of the magnetY 90, pulling itout of position, the fly dog 92 moves over against the iixed stop 92. Inthis position, it has moved one and a fraction tooth spaces-sucientto'skip the next tooth and allow it to re-enter the star wheel andarrest same on the second next tooth instead of the next tooth. In hisway, the carriage is allowed to move either one or two spaces at a time,as desired. Of course, it is self-evident that the little lever, B2b,may be operated by the nger instead of by outside power, if that isdesired, and I want full protection, whether this lever be manuallyoperated or power operated.

In the present typewriting machines, the carriage, when thrown back,strikes a positive rigid stop, which arrests its motion practicallyinstantly with a heavy bang, which is a nuisance to the operator andother people in the oiiice. This is particularly true where the carriageis returned by an outside power, and not by hand. This is entirelyunnecessary. In my machine, the marginal stop, instead of striking avrigid object and being brought instantly to rest, strikes a spring,dashpot or other shock--arresting device', which takes the most of themomentum out of the carriage in a very short travel and then allows thecarriage to be brought gently and quietly to a stop aga'inst the xedstop, so that it will always come to rest at the same point. Of course,very fast operators throw the carriage back faster than slow operators,and it is advisable to have an easy means of adjustment so that theindividual operator can quickly and easily adjust the spring or otherslowing down resistance to meet personal requirements.

This adjustment can be made easily and quickly either by adjusting theneedle valve of a dashpot, or by adjusting the screws, 93a, 93, in Fig.25, so as to bring the springs 94 and 948L closer to or further awayfrom the fixed stop 93. In this type of construction, I use two springs,one behind the other, the carriage first striking the spring 94a andpressing same against the spring 94, which, of course, materiallyincreases the resistance or carriage stopping action. The springs 94 and94a are tempered on an arc and stand away from the screws 93a, 93a,until the carriage moves them back against these screws, after which, ofcourse, as will be readily seen, the tension of the springs is very muchstiffer. The spring 94 has a hole in it sufliciently large to allow thescrew 93a to pass through it towards the spring 94, thereby giving eachspring an individual adjustment. As will be seen, due to the shorterlength of the spring 94 beyond this screw, it will be very much stifferthan the spring 94* in its rst position, but the spring 848L also willbecome much stiffer when it strikes the screw 83, on account of thegreatly reduced length of the springs above that point.

The noise suppressing device such as described may be mounted on thelever now commonly provided' on modern machines, rising from aprojectionvon the main frame, and against which the marginal stop abuts.Other mechanically equivalent constructions for this shock-arresting andnoise suppressing device may be employed such for example as a dashpothaving small apertures for releasing the air and a needle valve forcontrolling the balance of the air, or other spring arrangements suchfor example as a plurality of r concentric or otherwise disposedcompression springs of the coil type, projecting toward the carriage todifferent extents, so as to act successively and cumulatively. In thedescribed manner the noise of the bang of the carriage may be reduced toabout of that usual, by simple and inexpensive means which will work forlong periods and not get out of order.

Remarkable gain in speed due to using a legato touch Figs. 26 and 27show graphically the enormous gain in speed or work produced in a giventime, that results from using a genuine legato touch instead of astaccato touch. In every case the time represented by any of the linesa, a, is the same.

In Fig. 26, the top line represents twelve staccato actions or units oftime with the lowest possible loss between each action, and theoperators nger must be jerked up instantly in order to release the typebar which is rigidly connected to the finger key, and each action lmustbe completed before the next commences. The second line-the slantingline-made up of lines of exactly the same lengths as before, but whichoverlap each other only one-third, clearly shows how, still giving eachaction the same amount of time as before, but using an easy legato oroverlapping touch, with only one-third overlap, 50% more actions, oreighteen in all, are produced.

